[linux-lvm] LVM incredible slow with Kernel 2.6.11

From: Cristian Livadaru <drac3 vwclub ro>

To: linux-lvm redhat com

Subject: [linux-lvm] LVM incredible slow with Kernel 2.6.11

Date: Wed, 28 Jun 2006 11:24:27 +0200

I have built yesterday a 2.6.11 kernel with Xen.
I wanted to move some old data to my LVM and the speed according to
midnight commander was about 350kb/s ! about 2gig where copied in 4
hours! I then rebooted with the original Debian Kernel 2.4.27-2-386 and
the speed incresead to about 5mb/s that doesn't make me very happy
either but was way better then 350kb!
I have been searching the net all night and didn't come up with a
solution. I have no clue what is wrong here.
What did I do wrong and how can I increase the performance?
The lvm is made out of 2x Seagate 300GB IDE HD not striped.
esplendidos:~# lvm lvdisplay
--- Logical volume ---
LV Name /dev/share/sharevg
VG Name share
LV UUID KdvcJ9-ZLMP-AJYA-soGK-qHfy-UtrX-PpV9Kv
LV Write Access read/write
LV Status available
# open 1
LV Size 558.91 GB
Current LE 143082
Segments 2
Allocation inherit
Read ahead sectors 0
Block device 254:0
esplendidos:~# lvm dumpconfig
devices {
dir="/dev"
scan="/dev"
filter="r|/dev/cdrom|"
cache="/etc/lvm/.cache"
write_cache_state=1
sysfs_scan=1
md_component_detection=0
}
activation {
missing_stripe_filler="/dev/ioerror"
mirror_region_size=512
reserved_stack=256
reserved_memory=8192
process_priority=-18
}
global {
umask=63
test=0
activation=1
proc="/proc"
locking_type=1
locking_dir="/var/lock/lvm"
}
shell {
history_size=100
}
backup {
backup=1
backup_dir="/etc/lvm/backup"
archive=1
archive_dir="/etc/lvm/archive"
retain_min=10
retain_days=30
}
log {
verbose=0
syslog=1
overwrite=0
level=0
indent=1
command_names=0
prefix=" "
}
any tip for performance tuning?
--
Cristian Livadaru
http://vwclub.ro/